U.S. patent number 11,245,244 [Application Number 16/620,085] was granted by the patent office on 2022-02-08 for optical module and method for manufacturing the same.
This patent grant is currently assigned to Fujikura Ltd.. The grantee listed for this patent is FUJIKURA LTD.. Invention is credited to Akari Takahashi.
United States Patent |
11,245,244 |
Takahashi |
February 8, 2022 |
Optical module and method for manufacturing the same
Abstract
An optical module includes: an optical component; a base portion
on which the optical component is mounted; a housing that includes
sidewalls extending from the base portion in a height direction to
surround the base portion; a cover member that defines, along with
the housing, an accommodation space in which the optical component
is disposed; and a resin for fixing the housing to the cover
member. The cover member includes: an opposing surface that faces
the base portion of the housing in the height direction; a first
lateral cover surface extending along the height direction; and a
second lateral cover surface extending in the height direction. The
second lateral cover surface is disposed on an opposite side of the
first lateral cover surface.
Inventors: |
Takahashi; Akari (Sakura,
JP) |
Applicant: |
Name |
City |
State |
Country |
Type |
FUJIKURA LTD. |
Tokyo |
N/A |
JP |
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|
Assignee: |
Fujikura Ltd. (Tokyo,
JP)
|
Family
ID: |
1000006100461 |
Appl.
No.: |
16/620,085 |
Filed: |
May 17, 2018 |
PCT
Filed: |
May 17, 2018 |
PCT No.: |
PCT/JP2018/019035 |
371(c)(1),(2),(4) Date: |
December 06, 2019 |
PCT
Pub. No.: |
WO2019/008918 |
PCT
Pub. Date: |
January 10, 2019 |
Prior Publication Data
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|
|
Document
Identifier |
Publication Date |
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US 20200153198 A1 |
May 14, 2020 |
|
Foreign Application Priority Data
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|
|
|
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Jul 6, 2017 [JP] |
|
|
JP2017-132965 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01S
5/02208 (20130101); H01S 5/02326 (20210101); H01S
5/02234 (20210101) |
Current International
Class: |
H01S
5/02234 (20210101); H01S 5/02208 (20210101); H01S
5/02326 (20210101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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2005347341 |
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Dec 2005 |
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JP |
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2010050406 |
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Mar 2010 |
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JP |
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2010050406 |
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Mar 2010 |
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JP |
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2015130394 |
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Jul 2015 |
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JP |
|
2015130394 |
|
Jul 2015 |
|
JP |
|
I583086 |
|
May 2017 |
|
TW |
|
2013077199 |
|
May 2013 |
|
WO |
|
Other References
Supplementary European Search Report issued in corresponding
European Patent Application No. 18828496.2, dated Dec. 9, 2020 (6
pages). cited by applicant.
|
Primary Examiner: Nguyen; Tuan N
Attorney, Agent or Firm: Osha Bergman Watanabe & Burton
LLP
Claims
The invention claimed is:
1. An optical module comprising: an optical component; a base
portion on which the optical component is mounted; a housing that
comprises sidewalls extending from the base portion in a height
direction to surround the base portion; a cover member that
defines, along with the housing, an accommodation space in which
the optical component is disposed; and a resin for fixing the
housing to the cover member, wherein the cover member comprises: an
opposing surface that faces the base portion of the housing in the
height direction; a first lateral cover surface extending along the
height direction; and a second lateral cover surface extending
along the height direction, wherein the second lateral cover
surface is disposed on an opposite side of the first lateral cover
surface, the sidewalls of the housing comprise: a first sidewall
comprising a first counter portion having a first lateral counter
surface extending along the height direction; and a second sidewall
that faces the first sidewall, wherein the second sidewall
comprises a first cover support surface that supports the cover
member, and in at least one cross-section of the optical module on
a plane parallel to both the height direction and a first direction
perpendicular to the height direction: the first lateral counter
surface of the first sidewall of the housing faces the first
lateral cover surface of the cover member while the resin is
interposed therebetween, the second lateral cover surface of the
cover member is exposed to an outside of the optical module, and
the first cover support surface of the second sidewall of the
housing faces the opposing surface of the cover member.
2. The optical module according to claim 1, wherein the first
lateral counter surface of the first sidewall of the housing faces
the first lateral cover surface of the cover member over an overall
length of the first lateral counter surface while the resin is
interposed therebetween, and the second lateral cover surface of
the cover member is exposed to an outside of the optical module
over an overall length of the second lateral cover surface.
3. The optical module according to claim 1, wherein the housing
further comprises a counter corner that faces at least one corner
of the cover member.
4. The optical module according to claim 1, wherein a thickness of
the second lateral cover surface along the height direction is less
than a thickness of the first lateral cover surface along the
height direction.
5. The optical module according to claim 1, wherein the resin
comprises an ultraviolet curable resin.
6. The optical module according to claim 1, wherein the cover
member further comprises: a third lateral cover surface extending
along the height direction; and a fourth lateral cover surface
extending along the height direction, wherein the fourth lateral
cover surface is disposed on an opposite side of the third lateral
cover surface, the sidewalls of the housing further comprise: a
third sidewall comprising a second counter portion having a second
lateral counter surface extending along the height direction; and a
fourth sidewall that faces the third sidewall, wherein the fourth
sidewall comprises a second cover support surface that supports the
cover member, and in at least one cross-section of the optical
module on a plane parallel to both the height direction and a
second direction perpendicular to the height direction: the second
lateral counter surface of the third sidewall of the housing faces
the third lateral cover surface of the cover member while the resin
is interposed therebetween, the fourth lateral cover surface of the
cover member is exposed to the outside of the optical module, and
the second cover support surface of the fourth sidewall of the
housing faces the opposing surface of the cover member.
7. The optical module according to claim 6, wherein the second
lateral counter surface of the third sidewall of the housing faces
the third lateral cover surface of the cover member over an overall
length of the second lateral counter surface while the resin is
interposed therebetween, and the fourth lateral cover surface of
the cover member is exposed to an outside of the optical module
over an overall length of the fourth lateral cover surface.
8. The optical module according to claim 6, wherein the first
sidewall is disposed adjacent to the third sidewall.
9. The optical module according to claim 8, wherein the first
counter portion extends along the first sidewall from a connected
portion where the first sidewall is connected with the third
sidewall, and the second counter portion extends along the third
sidewall from the connected portion.
10. The optical module according to claim 6, wherein the housing
further comprises a counter corner that faces at least one corner
of the cover member.
11. The optical module according to claim 6, wherein a thickness of
the second lateral cover surface along the height direction is less
than a thickness of the first lateral cover surface along the
height direction.
12. The optical module according to claim 6, wherein the resin
comprises an ultraviolet curable resin.
13. The optical module according to claim 1, wherein the optical
component comprises at least one of a lens, a laser device, an
optical fiber, a ferrule, and a photodiode.
14. A method of manufacturing an optical module, the method
comprising: preparing a cover member that comprises: an opposing
surface; a first lateral cover surface perpendicular to the
opposing surface; and a second lateral cover surface perpendicular
to the opposing surface, wherein the second lateral cover surface
is disposed on an opposite side of the first lateral cover surface;
preparing a housing that comprises: a base portion; and sidewalls
extending from the base portion in a height direction to surround
the base portion, wherein the sidewalls are exposed to an outside
of the optical module, and the sidewalls of the housing comprise: a
first sidewall comprising a first counter portion having a first
lateral counter surface extending along the height direction; and a
second sidewall that faces the first sidewall and that comprises a
first cover support surface that supports the cover member,
mounting an optical component on the base portion; applying a resin
to a resin application area of the housing that includes the first
lateral counter surface of the first sidewall of the housing in at
least one cross-section of the housing on a plane parallel to both
the height direction and a first direction perpendicular to the
height direction; disposing the cover member to face the first
lateral counter surface of the first sidewall of the housing in a
state in which the opposing surface of the cover member faces the
base portion on which the optical component has been mounted to
bring the first lateral cover surface of the cover member into
contact with the resin applied to the first lateral counter surface
of the first sidewall of the housing, and also disposing the cover
member to face the first cover support surface of the second
sidewall of the housing; and curing the resin in a state in which
the first lateral cover surface of the cover member is brought into
contact with the resin applied to the first lateral counter surface
of the first sidewall of the housing.
15. The method of manufacturing an optical module according to
claim 14, wherein the resin comprises an ultraviolet curable resin,
and the curing of the resin comprises irradiating ultraviolet rays
onto the resin.
16. The method of manufacturing an optical module according to
claim 14, wherein the cover member further comprises: a third
lateral cover surface extending along the height direction; and a
fourth lateral cover surface extending along the height direction,
wherein the fourth lateral cover surface is disposed on an opposite
side of the third lateral cover surface, the sidewalls of the
housing further comprise: a third sidewall comprising a second
counter portion having a second lateral counter surface extending
along the height direction; and a fourth sidewall that faces the
third sidewall, wherein the fourth sidewall comprises a second
cover support surface that supports the cover member, and the resin
application area further includes the second lateral counter
surface of the third sidewall of the housing in at least one
cross-section of the housing on a plane parallel to both the height
direction and a second direction perpendicular to the height
direction, the disposing of the cover member to face the first
lateral counter surface and disposing the cover member to face the
cover support surface further comprises disposing the cover member
to face the second lateral counter surface of the third sidewall of
the housing to bring the third lateral cover surface of the cover
member into contact with the resin applied to the second lateral
counter surface of the third sidewall of the housing, and also
disposing the cover member to face the second cover support surface
of the fourth sidewall of the housing, and the curing of the resin
further comprises bringing the third lateral cover surface of the
cover member into contact with the resin applied to the second
lateral counter surface of the third sidewall of the housing.
17. The method of manufacturing an optical module according to
claim 16, wherein the resin comprises an ultraviolet curable resin,
and the curing of the resin comprises irradiating ultraviolet rays
onto the resin.
18. The method of manufacturing an optical module according to
claim 14, wherein the optical component comprises at least one of a
lens, a laser device, an optical fiber, a ferrule, and a
photodiode.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims benefit of priority from Japanese Patent
Application No. 2017-132965 filed on Jul. 6, 2017, the disclosure
of which is incorporated herein by reference. in its entirety.
TECHNICAL FIELD
The present invention relates to an optical module and a method of
manufacturing the same, and more particularly to an optical module
having a housing including an optical component mounted
thereon.
BACKGROUND
There has heretofore been known an optical module having a housing
including an optical component mounted thereon and a cover member
attached to the housing. As an example of such an optical module, a
laser module 901 as illustrated in FIG. 1 has been known in the art
(see, e.g., Patent Literature 1). The laser module 901 includes a
housing 910 having an opening portion formed therein and a cover
member 920 that covers the opening portion of the housing 910. The
housing 910 includes a base portion 911 and a sidewall 912
extending from an edge portion of the base portion 911. The
sidewall 912 has a recessed portion 913 formed at a top thereof.
Meanwhile, the cover member 920 has a projection portion 921 formed
at an edge portion of the cover member 920 so as to project toward
the sidewall 912 correspondingly to the recessed portion 913. The
cover member 920 is placed on the sidewall 912 of the housing 910
so that the projection portion 921 is received in the recessed
portion 913.
A resin 930 is formed between the projection portion 921 and the
recessed portion 913. The resin 930 is used to seal a gap between
the projection portion 921 and the recessed portion 913 and also to
fix the cover member 920 onto the housing 910. An accommodation
space S in which an optical component is placed is formed between
the housing 910 and the cover member 920. For example, optical
components such as a semiconductor laser device 941 operable to
emit a laser beam, an optical fiber 943, an optical coupling means
940 including lenses 942 and 944 for optically coupling the laser
beam to the optical fiber 943 are placed in the accommodation space
S.
In this laser module 901, the resin 930 seals the gap between the
housing 910 and the cover member 920. When the resin 930 expands
due to moisture absorption, the resin 930 deforms so that the
housing 910 is strongly pressed as illustrated by arrows in FIG. 1.
Thus, the housing 910 deforms as a result. If the housing 910
deforms in this manner, the optical components fixed to the housing
910 changes in position so that an optical axis of the laser beam
is misaligned. Therefore, the optical characteristics of the laser
module 901 are deteriorated.
PATENT LITERATURE
Patent Literature 1: JP 2015-130394 A
SUMMARY
One or more embodiments of the present invention provide an optical
module capable of maintaining optical characteristics of an optical
component placed in an accommodation space.
Furthermore, one or more embodiments of the present invention
provide a method of manufacturing an optical module capable of
maintaining optical characteristics of an optical component placed
in an accommodation space while it allows a cover member to be
positioned with accuracy.
According to one or more embodiments of the present invention,
there is provided an optical module capable of maintaining optical
characteristics of an optical component placed in an accommodation
space. The optical module has an optical component, a base portion
on which the optical component is mounted, a housing including
sidewalls extending from the base portion in a height direction so
as to surround the base portion, a cover member that defines, along
with the housing, an accommodation space in which the optical
component is placed, and a resin for fixing the housing and the
cover member to each other. The cover member includes an opposing
surface opposed to the base portion of the housing in the height
direction, a first lateral cover surface extending along the height
direction, and a second lateral cover surface extending along the
height direction and being located on an opposite side of the first
lateral cover surface. The sidewalls include a first sidewall
including a counter portion having a lateral counter surface
extending along the height direction and a second sidewall opposed
to the first sidewall. The second sidewall includes a cover support
surface for supporting the cover member. In at least one
cross-section among cross-sections of the optical module on a plane
parallel to both of a first direction perpendicular to the height
direction and the height direction, the lateral counter surface of
the counter portion of the first sidewall and the first lateral
cover surface are opposed to each other while the resin is
interposed therebetween, the second lateral cover surface of the
cover member is exposed to an outside, and the cover support
surface of the second sidewall and the opposing surface of the
cover member are opposed to each other. An ultraviolet curable
resin may be used for the resin.
In the specification, what is meant by the lateral cover surface
exposed to an outside is that the lateral cover surface faces an
external space while no resin is present outside of the lateral
cover surface, or while, if a housing is located outside of the
lateral cover surface, no resin is present between the lateral
cover surface and the housing.
With an optical module according to one or more embodiments of the
present invention, in at least one cross-section among
cross-sections of the optical module on a plane parallel to both of
the first direction and the height direction, the lateral counter
surface of the counter portion of the first sidewall and the first
lateral cover surface are opposed to each other while the resin is
interposed therebetween, the cover support surface of the second
sidewall and the opposing surface of the cover member are opposed
to each other, and the second lateral cover surface of the cover
member, which is on an opposite side of the first lateral cover
surface, is exposed to an outside. In other words, the resin is
provided only on one side of the cover member (on the first lateral
cover surface) in the first direction, and the second lateral cover
surface, which is on an opposite side of the first lateral cover
surface, is exposed to the outside. Therefore, the resin located
between the lateral counter surface of the counter portion of the
first sidewall and the first lateral cover surface of the cover
member can deform without any restriction in the first direction.
Accordingly, when the resin located between the lateral counter
surface of the counter portion of the first sidewall and the first
lateral cover surface of the cover member expands or shrinks in the
first direction, deformation of the resin exerts less influence on
the housing. Thus, the housing is prevented from deforming. As a
result, the optical characteristics of the optical component placed
in the accommodation space within the housing are prevented from
being deteriorated.
The lateral counter surface and the first lateral cover surface of
the cover member may be opposed to each other over an overall
length of the lateral counter surface of the counter portion of the
first sidewall while the resin is interposed therebetween. The
second lateral cover surface may be exposed to an outside over an
overall length of the second lateral cover surface located on an
opposite side of the first lateral cover surface. In this case, the
advantageous effect of preventing deformation of the housing can be
attained over the overall length of the first sidewall.
The cover member may further include a third lateral cover surface
extending along the height direction and a fourth lateral cover
surface extending along the height direction and being located on
an opposite side of the third lateral cover surface. In this case,
the sidewall may further include a third sidewall including a
counter portion having a lateral counter surface extending along
the height direction and a fourth sidewall opposed to the third
sidewall. The fourth sidewall may include a cover support surface
for supporting the cover member. In at least one cross-section
among cross-sections of the optical module on a plane parallel to
both of a second direction perpendicular to the height direction
and the height direction, the lateral counter surface of the
counter portion of the third sidewall and the third lateral cover
surface of the cover member may be opposed to each other while the
resin is interposed therebetween. The fourth lateral cover surface
of the cover member may be exposed to an outside, and the cover
support surface of the fourth sidewall and the opposing surface of
the cover member may be opposed to each other.
With this configuration, in at least one cross-section among
cross-sections of the optical module on a plane parallel to both of
the second direction and the height direction, the lateral counter
surface of the counter portion of the third sidewall and the third
lateral cover surface of the cover member are opposed to each other
while the resin is interposed therebetween, the cover support
surface of the fourth sidewall and the opposing surface of the
cover member are opposed to each other, and the fourth lateral
cover surface of the cover member, which is on an opposite side of
the third lateral cover surface, is exposed to an outside. In other
words, the resin is provided only on one side of the cover member
(on the third lateral cover surface) in the second direction, and
the fourth lateral cover surface, which is on an opposite side of
the third lateral cover surface, is exposed to the outside.
Therefore, the resin located between the lateral counter surface of
the counter portion of the third sidewall and the third lateral
cover surface of the cover member can deform without any
restriction in the second direction. Accordingly, when the resin
located between the lateral counter surface of the counter portion
of the third sidewall and the third lateral cover surface of the
cover member expands or shrinks in the second direction,
deformation of the resin exerts less influence on the housing.
Thus, the housing is prevented from deforming. As a result, the
optical characteristics of the optical component placed in the
accommodation space within the housing are prevented from being
deteriorated.
The lateral counter surface and the third lateral cover surface of
the cover member may be opposed to each other over an overall
length of the lateral counter surface of the counter portion of the
third sidewall while the resin is interposed therebetween, and the
fourth lateral cover surface may be exposed to an outside over an
overall length of the fourth lateral cover surface located on an
opposite side of the third lateral cover surface. In this case, the
advantageous effect of preventing deformation of the housing can be
attained over the overall length of the third sidewall.
The first sidewall and the third sidewall may be located adjacent
to each other. In this case, the counter portion of the first
sidewall may extend along the first sidewall from a connected
portion of the first sidewall and the third sidewall, and the
counter portion of the third sidewall may extend along the third
sidewall from the connected portion.
The housing may further include a counter corner portion (counter
corner) opposed to at least one corner portion (corner) of the
cover member. Provision of such a counter corner portion allows the
cover member to be positioned more accurately.
Furthermore, a thickness of the second lateral cover surface of the
cover member along the height direction may be less than a
thickness of the first lateral cover surface along the height
direction. When the thickness of the cover member is partially
reduced in the height direction, the weight of the optical module
can be reduced.
According to one or more embodiments of the present invention,
there is provided a method of manufacturing an optical module
capable of maintaining optical characteristics of an optical
component placed in an accommodation space while it allows a cover
member to be positioned with accuracy. In this method, a cover
member including an opposing surface, a first lateral cover surface
perpendicular to the opposing surface, and a second lateral cover
surface perpendicular to the opposing surface and being located on
an opposite side of the first lateral cover surface is prepared. A
housing including a base portion and sidewalls extending from the
base portion in a height direction so as to surround the base
portion is prepared. The sidewalls include a first sidewall
including a counter portion having a lateral counter surface
extending along the height direction and a second sidewall opposed
to the first sidewall. The second sidewall includes a cover support
surface for supporting the cover member. An optical component is
mounted on the base portion of the housing. A resin is applied to a
resin application area of the housing that includes the lateral
counter surface of the counter portion of the base portion in at
least one cross-section among cross-sections of the housing on a
plane parallel to both of a first direction perpendicular to the
height direction and the height direction. The cover member is
placed so as to face the lateral counter surface of the counter
portion of the first sidewall in a state in which the opposing
surface of the cover member is opposed to the base portion on which
the optical component has been mounted to bring the first lateral
cover surface of the cover member into contact with the resin
applied to the lateral counter surface, and the cover member is
also placed so as to face the cover support surface of the second
sidewall. The resin is cured in a state in which the first lateral
cover surface of the cover member is brought into contact with the
resin applied to the lateral counter surface of the counter portion
of the first sidewall.
With a method of manufacturing an optical module according to one
or more embodiments of the present invention, the cover member can
be positioned in the first direction by placing the cover member so
as to face the lateral counter surface of the counter portion of
the first sidewall. Furthermore, the resin is provided only on one
side of the cover member (on the first lateral cover surface) in
the first direction, and the second lateral cover surface, which is
on an opposite side of the first lateral cover surface, is exposed
to the outside. Therefore, the resin located between the lateral
counter surface of the counter portion of the first sidewall and
the first lateral cover surface of the cover member can deform
without any restriction in the first direction. Accordingly, when
the resin located between the lateral counter surface of the
counter portion of the first sidewall and the first lateral cover
surface of the cover member expands or shrinks in the first
direction, deformation of the resin exerts less influence on the
housing. Thus, the housing is prevented from deforming. As a
result, the optical characteristics of the optical component placed
in the accommodation space within the housing are prevented from
being deteriorated.
The cover member may further include a third lateral cover surface
extending along the height direction and a fourth lateral cover
surface extending along the height direction and being located on
an opposite side of the third lateral cover surface. The sidewalls
may further include a third sidewall including a counter portion
having a lateral counter surface extending along the height
direction and a fourth sidewall opposed to the third sidewall. The
fourth sidewall may include a cover support surface for supporting
the cover member. In this case, the resin application area further
includes the lateral counter surface of the counter portion of the
third sidewall in at least one cross-section among cross-sections
of the housing on a plane parallel to both of a second direction
perpendicular to the height direction and the height direction. The
placing the cover member so as to face the lateral counter surface
of the counter portion of the first sidewall and also placing the
cover member so as to face the cover support surface of the second
sidewall may comprise placing the cover member so as to face the
lateral counter surface of the counter portion of the third
sidewall to bring the third lateral cover surface of the cover
member into contact with the resin applied to the lateral counter
surface and also placing the cover member so as to face the cover
support surface of the fourth sidewall. The curing the resin may
comprise bringing the third lateral cover surface of the cover
member into contact with the resin applied to the lateral counter
surface of the counter portion of the third sidewall.
The cover member can be positioned in the second direction by
placing the cover member so as to face the lateral counter surface
of the counter portion of the third sidewall. Thus, the cover
member can be positioned in two directions including the first
direction and the second direction. Furthermore, the resin is
provided only on one side of the cover member (on the third lateral
cover surface) in the second direction, and the fourth lateral
cover surface, which is on an opposite side of the third lateral
cover surface, is exposed to the outside. Therefore, the resin
located between the lateral counter surface of the counter portion
of the third sidewall and the third lateral cover surface of the
cover member can deform without any restriction in the second
direction. Accordingly, when the resin located between the lateral
counter surface of the counter portion of the third sidewall and
the third lateral cover surface of the cover member expands or
shrinks in the second direction, deformation of the resin exerts
less influence on the housing. Thus, the housing is prevented from
deforming. As a result, the optical characteristics of the optical
component placed in the accommodation space within the housing are
prevented from being deteriorated.
An ultraviolet curable resin may be used for the resin. The resin
may be cured by irradiating ultraviolet rays into the resin.
According to one or more embodiments of the present invention, a
sealing member between the sidewalls and the cover member can be
arranged so as to extend along a plane toward an inside of the
housing from a portion where it is exposed to the outside.
Therefore, by irradiation along the plane from the outside,
ultraviolet rays can be introduced into the interior of the resin.
Accordingly, an ultraviolet curable resin, which can achieve
short-time curing, can be used as the resin. Thus, a throughput for
manufacturing the optical module can be improved.
One or more embodiments of the present invention provide an optical
module capable of maintaining optical characteristics of an optical
component placed in an accommodation space. Furthermore, there is
provided a method of manufacturing an optical module capable of
maintaining optical characteristics of an optical component placed
in an accommodation space while it allows a cover member to be
positioned with accuracy.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic cross-sectional view showing an example of a
conventional optical module.
FIG. 2 is a perspective view showing a laser module as an optical
module according to one or more embodiments of the present
invention.
FIG. 3 is a schematic cross-sectional view of the laser module
shown in FIG. 2.
FIG. 4 is an exploded perspective view of a portion of the laser
module shown in FIG. 2.
FIG. 5A is a perspective view explanatory of a process of
assembling a laser module shown in FIG. 2.
FIG. 5B is a perspective view explanatory of a process of
assembling a laser module shown in FIG. 2.
FIG. 5C is a perspective view explanatory of a process of
assembling a laser module shown in FIG. 2.
FIG. 6 is an exploded perspective view of a portion of a laser
module according to one or more embodiments of the present
invention.
FIG. 7 is an exploded perspective view of a portion of a laser
module according to one or more embodiments of the present
invention.
FIG. 8 is an exploded perspective view of a portion of a laser
module according to one or more embodiments of the present
invention.
FIG. 9 is a perspective view showing a laser module according to
one or more embodiments of the present invention.
FIG. 10 is an exploded perspective view of a portion of the laser
module shown in FIG. 9.
FIG. 11 is a perspective view showing a laser module according to
one or more embodiments of the present invention.
FIG. 12 is an exploded perspective view of a portion of the laser
module shown in FIG. 11.
FIG. 13 is an exploded perspective view of a laser module according
to one or more embodiments of the present invention.
FIG. 14 is an exploded perspective view showing a variation of the
laser module shown in FIG. 4.
DETAILED DESCRIPTION
Embodiments of an optical module according to the present invention
will be described in detail below with reference to FIGS. 2 to 14.
In the following, a laser module using a semiconductor laser device
will be described as an example of an optical module according to
the present invention. Nevertheless, the present invention is
applicable to an optical module using any optical component other
than a semiconductor laser device. In FIGS. 2 to 14, the same or
corresponding components are denoted by the same or corresponding
reference numerals and will not be described below repetitively.
Furthermore, in FIGS. 2 to 14, the scales or dimensions of
components may be exaggerated, or some components may be
omitted.
FIG. 2 is a perspective view showing a laser module 1 as an optical
module according to one or more embodiments of the present
invention, and FIG. 3 is a schematic cross-sectional view of the
laser module 1. As shown in FIGS. 2 and 3, the laser module 1
includes a housing 10 in the form of a generally rectangular
parallelepiped, which is opened in the +Z-direction, and a cover
member 20 in the form of a generally flat plate. The housing 10
includes a base portion 12 in the form of a flat plate and
sidewalls 31-34 extending from the base portion 12 in the
Z-direction (height direction) so as to surround the base portion
12. An opening portion of the housing 10, which is in the form of a
generally rectangular parallelepiped, is covered with the cover
member 20 to form an accommodation space S within the housing 10.
The base portion 12 may be placed on a heat sink, which is not
illustrated. Alternatively, the base portion 12 may include one or
more water-cooled tubes.
Optical components are fixed on a front surface 12A of the base
portion 12 of the housing 10. In an example illustrated in FIG. 3,
a semiconductor laser device 40 and optical coupling means 43
including lenses 41 and 42 are fixed as optical components on the
front surface 12A of the base portion 12. Furthermore, a ferrule
fixation portion 44 is also fixed on the front surface 12A of the
base portion 12. A ferrule 45 is placed on the ferrule fixation
portion 44. The ferrule 45 holds an optical fiber 46 as an optical
component. Those components are placed in the accommodation space S
within the housing 10. Those components are fixed to the base
portion 12 of the housing 10 or to the ferrule fixation portion 44
with, for example, an adhesive material.
FIG. 4 is a perspective view of the laser module 1 when the housing
10 and the cover member 20 are disassembled. For the sake of
simplification, the aforementioned components 40-46 are omitted
from the illustration. As shown in FIG. 4, the sidewall 31 (first
sidewall) has a cover support surface 51 for supporting the cover
member 20 and a counter portion 61 extending in the +Z-direction
from an outside (-X side) of the cover support surface 51. The
counter portion 61 has a lateral counter surface 61A extending in
the +Z-direction from the cover support surface 51 and in parallel
to the YZ-plane. The sidewall 32 (second sidewall) has a cover
support surface 52 on its top for supporting the cover member 20.
The sidewall 33 (third sidewall) has a cover support surface 53 for
supporting the cover member 20 and a counter portion 63 extending
in the +Z-direction from an outside (-Y side) of the cover support
surface 53. The counter portion 63 has a lateral counter surface
63A extending in the +Z-direction from the cover support surface 53
and in parallel to the XZ-plane. The sidewall 34 (fourth sidewall)
has a cover support surface 54 on its top for supporting the cover
member 20.
The sidewall 31 and the sidewall 32 are opposed to each other in
the X-direction. The sidewall 33 and the sidewall 34 are opposed to
each other in the Y-direction. The sidewall 31 and the sidewall 33
are located adjacent to each other. The counter portion 61 of the
sidewall 31 and the counter portion 63 of the sidewall 33 intersect
each other at a connected portion of the sidewall 31 and the
sidewall 33. Specifically, the counter portion 61 of the sidewall
31 extends in the +Y-direction from the connected portion of the
sidewall 31 and the sidewall 33 over the overall length of the
sidewall 31. The counter portion 63 of the sidewall 33 extends in
the +X-direction from the connected portion of the sidewall 31 and
the sidewall 33 over the overall length of the sidewall 33.
As shown in FIGS. 3 and 4, the cover member 20 has four lateral
cover surfaces 21-24 extending in the Z-direction, an opposing
surface 25 opposed to the base portion 12 of the housing 10 in the
Z-direction, and a front surface 26 located on an opposite side of
the opposing surface 25 in the Z-direction. The lateral cover
surface 21 (first lateral cover surface) and the lateral cover
surface 22 (second lateral cover surface) are in parallel to the
YZ-plane and are opposed to each other in the X-direction.
Furthermore, the lateral cover surface 23 (third lateral cover
surface) and the lateral cover surface 24 (fourth lateral cover
surface) are in parallel to the XZ-plane and are opposed to each
other in the Y-direction.
As shown in FIG. 2, a resin 70 is disposed between the sidewalls
31-34 of the housing 10 and the cover member 20 over the whole
circumference of the housing 10. More specifically, the resin 70 is
provided continuously between a lateral counter surface 61A of the
counter portion 61 of the sidewall 31 (see FIG. 4) and the lateral
cover surface 21 of the cover member 20 (see FIG. 4), between a
lateral counter surface 63A of the counter portion 63 of the
sidewall 33 (FIG. 4) and the lateral cover surface 23 of the cover
member 20 (see FIG. 4), between the cover support surface 52 of the
sidewall 32 (see FIG. 4) and the opposing surface 25 of the cover
member 20 (see FIG. 3), and between the cover support surface 54 of
the sidewall 34 (see FIG. 4) and the opposing surface 25 of the
cover member 20 (see FIG. 3).
In this laser module 1, if moisture gets into the accommodation
space S in which the optical components have been placed, then the
adhesive material that fixes the optical components to the housing
10 may be deteriorated by hydrolysis, resulting in lowered adhesive
strength. Alternatively, dew condensation may be caused in the
accommodation space S so as to deteriorate the optical
characteristics of the optical components. Therefore, it is
important to sufficiently seal the accommodation space S within the
laser module 1. According to one or more embodiments, as described
above, the resin 70 is disposed between the sidewalls 31-34 of the
housing 10 and the cover member 20 over the whole circumference of
the housing 10. Accordingly, the resin 70 allows the accommodation
space S in the laser module 1 to be sealed for moisture prevention.
Examples of the resin 70 include ultraviolet curable resin, which
will be described later, heat curable resin, moisture curable
resin, anaerobic curable resin, and the like.
According to one or more embodiments, for example, with regard to
the XZ-plane as shown in FIG. 3, the lateral counter surface 61A of
the counter portion 61 of the sidewall 31 and the lateral cover
surface 21 of the cover member 20 are opposed to each other while
the resin 70 is interposed therebetween. The cover support surface
52 of the sidewall 32 and the opposing surface 25 of the cover
member 20 are opposed to each other while the resin 70 is
interposed therebetween. The lateral cover surface 22 of the cover
member 20, which is on an opposite side of the lateral cover
surface 21, is exposed to an outside. In other words, the resin 70
is provided only on one side of the cover member 20 (on the lateral
cover surface 21) in the X-direction, and the lateral cover surface
22, which is on an opposite side of the lateral cover surface 21,
is exposed to the outside. Therefore, the resin 70 located between
the lateral counter surface 61A of the counter portion 61 of the
sidewall 31 and the lateral cover surface 21 of the cover member 20
can deform without any restriction in the X-direction. Accordingly,
when the resin 70 located between the lateral counter surface 61A
of the counter portion 61 of the sidewall 31 and the lateral cover
surface 21 of the cover member 20 expands or shrinks in the
X-direction, deformation of the resin 70 exerts less influence on
the housing 10. Thus, the housing 10 is prevented from deforming.
As a result, the optical characteristics of the optical components
placed in the accommodation space S within the housing 10 are
prevented from being deteriorated.
Furthermore, those advantageous effects can also be attained with
regard to the YZ-plane. Specifically, the lateral counter surface
63A of the counter portion 63 of the sidewall 33 and the lateral
cover surface 23 of the cover member 20 are opposed to each other
while the resin 70 is interposed therebetween. The cover support
surface 54 of the sidewall 34 and the opposing surface 25 of the
cover member 20 are opposed to each other while the resin 70 is
interposed therebetween. The lateral cover surface 24 of the cover
member 20, which is on an opposite side of the lateral cover
surface 23, is exposed to an outside. In other words, the resin 70
is provided only on one side of the cover member 20 (on the lateral
cover surface 23) in the Y-direction, and the lateral cover surface
24, which is on an opposite side of the lateral cover surface 23,
is exposed to the outside. Therefore, the resin 70 located between
the lateral counter surface 63A of the counter portion 63 of the
sidewall 33 and the lateral cover surface 23 of the cover member 20
can deform without any restriction in the Y-direction. Accordingly,
when the resin 70 located between the lateral counter surface 63A
of the counter portion 63 of the sidewall 33 and the lateral cover
surface 23 of the cover member 20 expands or shrinks in the
Y-direction, deformation of the resin 70 exerts less influence on
the housing 10. Thus, the housing 10 is prevented from deforming.
As a result, the optical characteristics of the optical components
placed in the accommodation space S within the housing 10 are
prevented from being deteriorated.
Particularly, according to one or more embodiments, the lateral
counter surface 61A and the lateral cover surface 21 of the cover
member 20 are opposed to each other over the overall length of the
lateral counter surface 61A of the counter portion 61 of the
sidewall 31 in the Y-direction while the resin 70 is interposed
therebetween. The lateral cover surface 22 opposite to the lateral
cover surface 21 is exposed to the outside over the overall length
of the lateral cover surface 22 in the Y-direction. Therefore, the
advantageous effect of preventing deformation of the housing 10 can
be attained over the overall length of the sidewall 31 in the
Y-direction. Similarly, the lateral counter surface 63A and the
lateral cover surface 23 of the cover member 20 are opposed to each
other over the overall length of the lateral counter surface 63A of
the counter portion 63 of the sidewall 33 in the X-direction while
the resin 70 is interposed therebetween. The lateral cover surface
24 opposite to the lateral cover surface 23 is exposed to the
outside over the overall length of the lateral cover surface 24 in
the X-direction. Therefore, the advantageous effect of preventing
deformation of the housing 10 can be attained over the overall
length of the sidewall 33 in the X-direction.
Since the influence of deformation of the resin 70 on the housing
10 can thus be reduced, a hard resin can be used as the resin 70.
Resins having a low moisture permeability generally tend to be
hard. According to one or more embodiments, such a resin having a
low moisture permeability can be used as the resin 70. When such a
resin having a low moisture permeability is used as the resin 70,
moisture prevention can be enhanced for the accommodation space S
within the laser module 1.
Now a method of manufacturing a laser module 1 thus constructed
will be described. First, the aforementioned housing 10 is
prepared. The aforementioned optical components 40-46 are mounted
on the base portion 12 of the housing 10. As shown in FIG. 5A, a
resin 70 is applied onto a resin application area (shaded area in
FIG. 5A), which includes the lateral counter surface 61A of the
counter portion 61 of the sidewall 31, the lateral counter surface
63A of the counter portion 63 of the sidewall 33, the cover support
surface 52 of the sidewall 32, and the cover support surface 54 of
the sidewall 34. In this example, an ultraviolet curing resin is
used as the resin 70. In FIGS. 5A-5C, components other than the
housing 10 and the cover member 20 are omitted from illustration
for better understanding.
Next, the aforementioned cover member 20 is prepared. The opposing
surface 25 of the cover member 20 (see FIG. 3) is opposed to the
base portion 12 of the housing 10 (the state illustrated in FIG.
4). In this state, as shown in FIG. 5B, the cover member 20 is
placed so as to face the lateral counter surface 61A of the counter
portion 61 of the sidewall 31 (P1) and is also placed so as to face
the lateral counter surface 63A of the counter portion 63 of the
sidewall 33 (P2). Thus, the lateral cover surface 21 of the cover
member 20 is brought into contact with the resin 70 applied onto
the lateral counter surface 61A, and the lateral cover surface 23
of the cover member 20 is brought into contact with the resin 70
applied onto the lateral counter surface 63A. Furthermore, the
cover member 20 is pushed toward the cover support surface 52 of
the sidewall 32 (P3) and is also pushed toward the cover support
surface 54 of the sidewall 34 (P4). Thus, the opposing surface 25
of the cover member 20 is brought into contact with the resin 70
applied onto the cover support surfaces 52 and 54 of the sidewalls
32 and 34.
At that time, the cover member 20 can be positioned in the
X-direction by placing the cover member 20 so as to face the
lateral counter surface 61A of the counter portion 61 of the
sidewall 31. The cover member 20 can be positioned in the
Y-direction by placing the cover member 20 so as to face the
lateral counter surface 63A of the counter portion 63 of the
sidewall 33. Thus, according to one or more embodiments, the cover
member 20 can be positioned with accuracy on the XY-plane.
In this state, as shown in FIG. 5C, ultraviolet rays are irradiated
to the resin 70 in all possible directions with use of an
ultraviolet irradiation apparatus (UV furnace) or the like. At that
time, the resin 70 located between the sidewall 31 and the cover
member 20 is exposed to the outside on the +Z side while it extends
along the YZ-plane. Therefore, the resin 70 located between the
sidewall 31 and the cover member 20 can be cured by ultraviolet
rays (V1) irradiated along the YZ-plane. Furthermore, the resin 70
located between the sidewall 32 and the cover member 20 is exposed
to the outside on the +X side while it extends along the XY-plane.
Therefore, the resin 70 located between the sidewall 32 and the
cover member 20 can be cured by ultraviolet rays (V2) irradiated
along the XY-plane. Moreover, the resin 70 located between the
sidewall 33 and the cover member 20 is exposed to the outside on
the +Z side while it extends along the XZ-plane. Therefore, the
resin 70 located between the sidewall 33 and the cover member 20
can be cured by ultraviolet rays (V3) irradiated along the
XZ-plane. Furthermore, the resin 70 located between the sidewall 34
and the cover member 20 is exposed to the outside on the +Y side
while it extends along the XY-plane. Therefore, the resin 70
located between the sidewall 34 and the cover member 20 can be
cured by ultraviolet rays (V4) irradiated along the XY-plane.
Thus, according to one or more embodiments, the resin 70 located
between the sidewalls 31-34 and the cover member 20 is arranged so
as to extend along a plane toward an inside of the housing 10 from
a portion where it is exposed to the outside. Therefore, by
irradiation along the plane from the outside, ultraviolet rays can
be introduced into the interior of the resin 70. Accordingly, an
ultraviolet curable resin, which can achieve short-time curing, can
be used as the resin 70. Thus, a throughput for manufacturing the
laser module 1 can be improved. In the structure of the
conventional example shown in FIG. 1, no ultraviolet rays can be
irradiated to the resin 930 located near the accommodation space S
from the outside. Therefore, an ultraviolet curable resin cannot be
used as the resin 930.
According to one or more embodiments, the sidewall 31 includes the
counter portion 61 and the cover support surface 51, and the
sidewall 33 includes the counter portion 63 and the cover support
surface 53. For example, as shown in FIG. 6, the cover support
surface 51 of the sidewall 31 may be omitted so that the sidewall
31 only includes the counter portion 61. Similarly, the cover
support surface 53 of the sidewall 33 may be omitted so that the
sidewall 33 only includes the counter portion 63.
According to one or more embodiments, the aforementioned
advantageous effects of preventing deformation of the housing 10
can be attained on any cross-sections of the housing 10 and the
cover member 20 that are parallel to the XZ-plane and also on any
cross-sections of the housing 10 and the cover member 20 that are
parallel to the YZ-plane. As shown in FIG. 7, however, a counter
portion 64 may also be formed on the sidewall 34 so that the
aforementioned advantageous effects of preventing deformation of
the housing 10 is attained only on cross-sections of the housing 10
and the cover member 20 that are parallel to the XZ-plane. In this
case, the resin 70 is provided on only one side of the cover member
20 in the X-direction (on the side of the lateral cover surface 21)
while the opposite lateral cover surface 22 is exposed to the
outside. Therefore, the resin 70 located between the lateral
counter surface 61A of the counter portion 61 of the sidewall 31
and the lateral cover surface 21 of the cover member 20 can deform
in the X-direction without any restriction, so that the
aforementioned advantageous effects of preventing deformation of
the housing 10 can be attained.
Additionally, as shown in FIG. 8, a counter portion 62 may also be
formed on a portion of the sidewall 32, for example, so that the
aforementioned advantageous effects of preventing deformation of
the housing 10 can be attained on only part of cross-sections of
the housing 10 and the cover member 20 that are parallel to the
XZ-plane. In the example illustrated in FIG. 8, a protrusion 27 is
formed on the cover member 20 so as to correspond to a portion
where the counter portion 62 is not formed. A lateral cover surface
27A of the protrusion 27 is exposed to the outside. Therefore, with
regard to cross-sections of the housing 10 and the cover member 20
that are parallel to the XZ-plane and pass through the protrusion
27, the resin 70 is provided on only one side of the cover member
20 in the X-direction (on the side of the lateral cover surface 21)
while the opposite lateral cover surface 27A is exposed to the
outside. Therefore, the resin 70 located between the lateral
counter surface 61A of the counter portion 61 of the sidewall 31
and the lateral cover surface 21 of the cover member 20 can deform
in the X-direction without any restriction, so that the
aforementioned advantageous effects of preventing deformation of
the housing 10 can be attained. Thus, the housing 10 and the cover
member 20 can be configured such that the aforementioned
advantageous effects of preventing deformation of the housing 10
can be attained on at least one cross-section that is parallel to
the Z-direction.
FIG. 9 is a perspective view showing a laser module 301 according
to one or more embodiments of the present invention, and FIG. 10 is
a perspective view of the laser module 301 when the laser module
301 is disassembled. In FIG. 10, components of the laser module 301
other than the housing 310 and the cover member 20 are omitted from
illustration for better understanding.
The housing 310 of the laser module 301 includes a counter corner
portion 331 extending along the +X-direction from an end of the
counter portion 61 on the +Y side, a counter corner portion 332
extending along the +Y-direction from an end of the counter portion
63 on the +X side, a counter corner portion 333 extending along the
-Y-direction from a connected portion of the sidewall 32 and the
sidewall 34, and a counter corner portion 334 extending along the
-X-direction from the connected portion of the sidewall 32 and the
sidewall 34. The counter corner portion 331 and the counter corner
portion 334 project from the cover support surface 54 in the
+Z-direction. The counter corner portion 332 and the counter corner
portion 333 project from the cover support surface 52 in the
+Z-direction.
The counter corner portion 331 is configured to face the lateral
cover surface 24 of a corner portion C1 of the cover member 20. The
counter corner portion 332 is configured to face the lateral cover
surface 22 of a corner portion C2 of the cover member 20.
Furthermore, the counter corner portion 333 is configured to face
the lateral cover surface 22 of a corner portion C3 of the cover
member 20. The counter corner portion 334 is configured to face the
lateral cover surface 24 of the corner portion C3 of the cover
member 20. In other words, according to one or more embodiments,
the counter corner portions 331-334 are provided so as to face all
of the corner portions C1-C4 of the cover member 20.
When the cover member 20 is placed on the cover support surfaces
51-54 with those counter corner portions 331-334, the corner
portion C1 of the cover member 20 is positioned by the counter
corner portion 331, the corner portion C2 is positioned by the
counter corner portion 332, and the corner portion C3 is positioned
by the counter corner portions 333 and 334. Thus, provision of the
counter corner portions 331-334 allows the cover member 20 to be
positioned more accurately on the XY-plane. Particularly, in the
present embodiments, the counter corner portions 331-334 are
provided so as to face all of the corner portions C1-C4 of the
cover member 20. Therefore, the position of the cover member 20 is
stably maintained. In this example, the resin 70 is applied to a
shaded area in FIG. 10 to fix the cover member 20 onto the housing
310.
In the aforementioned embodiments, the counter portion 61 of the
sidewall 31 does not need to be formed over the overall length of
the sidewall 31 in the Y-direction. The counter portion 63 of the
sidewall 33 does not need to be formed over the overall length of
the sidewall 33 in the X-direction. Such examples will be described
in one or more embodiments.
FIG. 11 is a perspective view showing a laser module 101 according
to one or more embodiments of the present invention, and the FIG.
12 is a perspective view of the laser module 101 when the laser
module 101 is disassembled. In FIG. 12, components other than a
housing 110 and a cover member 120 of the laser module 101 are
omitted from illustration for better understanding.
The laser module 101 includes a housing 110 in the form of a
generally rectangular parallelepiped, which is opened in the
+Z-direction, and a cover member 120 in the form of a generally
flat plate. The housing 110 includes sidewalls 131-134 extending
from the base portion 12 in the Z-direction (height direction) so
as to surround the base portion 12. The sidewall 131 (first
sidewall) has a cover support surface 151 for supporting the cover
member 120 and a counter portion 161 extending in the +Z-direction
from the -Y side of the cover support surface 151. The counter
portion 161 has a lateral counter surface 161A extending in the
+Z-direction and in parallel to the YZ-plane and a lateral counter
surface 161B extending in the +Z-direction from the cover support
surface 151 and in parallel to the XZ-plane. The sidewall 132
(second sidewall) has a cover support surface 152 on its top for
supporting the cover member 120. The sidewall 133 (third sidewall)
has a cover support surface 153 for supporting the cover member 120
and a counter portion 163 extending in the +Z-direction on the -X
side of the cover support surface 153. The counter portion 163 has
a lateral counter surface 163A extending in the +Z-direction and in
parallel to the XZ-plane and a lateral counter surface 163B
extending in the +Z-direction from the cover support surface 153
and in parallel to the YZ-plane. The sidewall 134 (fourth sidewall)
has a cover support surface 154 on its top for supporting the cover
member 120.
The counter portion 161 of the sidewall 131 and the counter portion
163 of the sidewall 133 intersect each other at a connected portion
of the sidewall 131 and the sidewall 133. The counter portion 161
of the sidewall 131 extends in the +Y-direction from the connected
portion of the sidewall 131 and the sidewall 133 by a predetermined
distance. The counter portion 163 of the sidewall 133 extends in
the +X-direction from the connected portion of the sidewall 131 and
the sidewall 133 by a predetermined distance.
As shown in FIG. 12, the cover member 120 includes eight lateral
cover surfaces 121-128 extending in the Z-direction, an opposing
surface 129 opposed to the base portion 12 of the housing 110 in
the Z-direction, and a front surface 130 located on an opposite
side of the opposing surface 129 in the Z-direction. The lateral
cover surface 121 (first lateral cover surface) and the lateral
cover surface 122 (second lateral cover surface) are in parallel to
the YZ-plane and are located opposite to each other in the
X-direction. The lateral cover surface 123 (third lateral cover
surface) and the lateral cover surface 124 (fourth lateral cover
surface) are in parallel to the XZ-plane and are located opposite
to each other in the Y-direction. The lateral cover surfaces 125
and 126 are in parallel to the YZ-plane and are located on an
opposite side of the lateral cover surface 122 in the X-direction.
Furthermore, the lateral cover surfaces 127 and 128 are in parallel
to the XZ-plane and located on an opposite side of the lateral
cover surface 124 in the Y-direction. Thus, the cover member 120
according to one or more embodiments has a shape in which an
L-shaped portion that corresponds to the counter portions 161 and
163 of the housing 110 has been removed from a rectangular plate
member.
As shown in FIG. 11, a resin 70 is disposed between the sidewalls
131-134 of the housing 110 and the cover member 120 over the whole
circumference of the housing 110. More specifically, the resin 70
is provided continuously between a lateral counter surface 161A of
the counter portion 161 of the sidewall 131 and the lateral cover
surface 121 of the cover member 120, between a lateral counter
surface 163A of the counter portion 163 of the sidewall 133 and the
lateral cover surface 123 of the cover member 120, between a
lateral counter surface 163B of the counter portion 163 of the
sidewall 133 and the lateral cover surface 125 of the cover member
120, between the cover support surface 153 of the sidewall 133 and
the opposing surface 129 of the cover member 120, between the cover
support surface 152 of the sidewall 132 and the opposing surface
129 of the cover member 120, between the cover support surface 154
of the sidewall 134 and the opposing surface 129 of the cover
member 120, between the cover support surface 151 of the sidewall
131 and the opposing surface 129 of the cover member 120, and
between a lateral counter surface 161B of the counter portion 161
of the sidewall 131 and the lateral cover surface 127 of the cover
member 120. Thus, the resin 70 is disposed between the sidewalls
131-134 of the housing 110 and the cover member 120 over the whole
circumference of the housing 110. Accordingly, the resin 70 allows
the accommodation space S in the laser module 101 to be sealed for
moisture prevention.
With regard to cross-sections that are parallel to the XZ-plane and
pass through the counter portion 161 of the sidewall 131, the
lateral counter surface 161A of the counter portion 161 of the
sidewall 131 and the lateral cover surface 121 of the cover member
120 are opposed to each other while the resin 70 is interposed
therebetween. The cover support surface 152 of the sidewall 132 and
the opposing surface 129 of the cover member 120 are opposed to
each other while the resin 70 is interposed therebetween. The
lateral cover surface 122 of the cover member 120, which is located
on an opposite side of the lateral cover surface 121, is exposed to
an outside. In other words, the resin 70 is provided only on one
side of the cover member 120 (on the lateral cover surface 121) in
the X-direction, and the lateral cover surface 122, which is on an
opposite side of the lateral cover surface 121, is exposed to the
outside. Therefore, the resin 70 located between the lateral
counter surface 161A of the counter portion 161 of the sidewall 131
and the lateral cover surface 121 of the cover member 120 can
deform without any restriction in the X-direction. Accordingly,
when the resin 70 located between the lateral counter surface 161A
of the counter portion 161 of the sidewall 131 and the lateral
cover surface 121 of the cover member 120 expands or shrinks in the
X-direction, deformation of the resin 70 exerts less influence on
the housing 110. Thus, the housing 110 is prevented from deforming.
As a result, the optical characteristics of the optical components
placed in the accommodation space S within the housing 110 are
prevented from being deteriorated. Such advantageous effects can be
attained in the same manner with regard to cross-sections that are
parallel to the YZ-plane and pass through the counter portion 163
of the sidewall 133.
When a laser module 101 thus constructed is manufactured, a resin
70 is applied onto a resin application area shaded in FIG. 12 (the
cover support surface 151 of the sidewall 131, the lateral counter
surfaces 161A and 161B of the counter portion 161 of the sidewall
131, the lateral counter surfaces 163A and 163B of the counter
portion 163 of the sidewall 133, the cover support surface 153 of
the sidewall 133, the cover support surface 152 of the sidewall
132, and the cover support surface 154 of the sidewall 134). As
with the above-described embodiments, an ultraviolet curable resin
can be used for the resin 70.
In a state in which the opposing surface 129 of the cover member
120 is opposed to the base portion 12 of the housing 110, the cover
member 120 is placed so as to face the lateral counter surface 161A
of the counter portion 161 of the sidewall 131 and the lateral
counter surface 163B of the counter portion 163 of the sidewall
133. The cover member 120 is also placed so as to face the lateral
counter surface 163A of the counter portion 163 of the sidewall 133
and the lateral counter surface 161B of the counter portion 161 of
the sidewall 131. Thus, the lateral cover surfaces 121, 125, 123,
and 127 of the cover member 120 are brought into contact with the
resin 70 applied onto the lateral counter surfaces 161A, 163B,
163A, and 161B, respectively. Furthermore, the cover member 120 is
pushed toward the cover support surfaces 151-154 of the sidewalls
131-134. Thus, the opposing surface 129 of the cover member 120 is
brought into contact with the resin 70 applied onto the cover
support surfaces 151-154 of the sidewalls 131-134.
At that time, the cover member 120 can be positioned in the
X-direction by placing the cover member 120 so as to face the
lateral counter surface 161A of the counter portion 161 of the
sidewall 131 and the lateral counter surface 163B of the counter
portion 163 of the sidewall 133. The cover member 120 can be
positioned in the Y-direction by placing the cover member 120 so as
to face the lateral counter surface 163A of the counter portion 163
of the sidewall 133 and the lateral counter surface 161B of the
counter portion 161 of the sidewall 131. Thus, according to one or
more embodiments, the cover member 120 can be positioned with
accuracy on the XY-plane.
In this state, ultraviolet rays are irradiated to the resin 70 in
all possible directions with use of an ultraviolet irradiation
apparatus (UV furnace) or the like. At that time, the resin 70
located between the sidewalls 131-134 and the cover member 120
extends from an externally exposed portion along the YZ-plane, the
XZ-plane, or the XY-plane. Therefore, the resin 70 located between
the sidewalls 131-134 and the cover member 120 can be cured by
ultraviolet rays irradiated along the YZ-plane, the XZ-plane, or
the XY-plane. Therefore, all of the resin 70 located between the
sidewalls 131-134 and the cover member 120 can be cured by
ultraviolet rays irradiated from the outside.
FIG. 13 is a perspective view of a laser module according to one or
more embodiments of the present invention when the laser module is
disassembled. In FIG. 13, components other than a housing 210 and a
cover member 220 of the laser module are omitted from illustration
for better understanding. The present embodiments correspond to
those in which the length of the counter portion 161 of the
sidewall 131 along the Y-direction and the length of the counter
portion 163 of the sidewall 133 along the X-direction have been
shortened from the those in the embodiments described above.
The laser module includes a housing 210 in the form of a generally
rectangular parallelepiped, which is opened in the +Z-direction,
and a cover member 220 in the form of a generally flat plate. The
housing 210 includes sidewalls 231-234 extending from the base
portion 12 in the Z-direction (height direction) so as to surround
the base portion 12. The sidewalls 231-234 have cover support
surfaces 251-254 for supporting the cover member 220, respectively.
According to one or more embodiments, a counter portion 260
extending in the +Z-direction is provided at a connected portion of
the sidewall 231 and the sidewall 233, which are located adjacent
to each other. The counter portion 260 is shared between the
sidewall 231 and the sidewall 233. The counter portion 260 has a
lateral counter surface 260A extending the +Z-direction from the
cover support surface 253 and in parallel to the YZ-plane and a
lateral counter surface 260B extending in +Z-direction from the
cover support surface 251 and in parallel to the XZ-plane.
The cover member 220 includes six lateral cover surfaces 221-226
extending in the Z-direction, an opposing surface 227 opposed to
the base portion 12 of the housing 210 in the Z-direction, and a
front surface 228 located on an opposite side of the opposing
surface 227 in the Z-direction. The lateral cover surface 221 and
the lateral cover surface 222 are in parallel to the YZ-plane and
are located opposite to each other in the X-direction. The lateral
cover surface 223 and the lateral cover surface 224 are in parallel
to the XZ-plane and are located opposite to each other in the
Y-direction. The lateral cover surface 225 is in parallel to the
YZ-plane and is located opposite to the lateral cover surface 222
in the X-direction. The lateral cover surface 226 is in parallel to
the XZ-plane and is located opposite to the lateral cover surface
224 in the Y-direction. Thus, the cover member 220 according to one
or more embodiments has a shape in which a rectangular portion that
corresponds to the counter portion 260 of the housing 210 has been
removed from a rectangular plate member.
According to one or more embodiments, a resin 70 is disposed
between the sidewalls 231-234 of the housing 210 and the cover
member 220 over the whole circumference of the housing 210. More
specifically, the resin 70 is provided continuously between the
lateral counter surface 260A of the counter portion 260 and the
lateral cover surface 221 of the cover member 220, between the
cover support surface 253 of the sidewall 233 and the opposing
surface 227 of the cover member 220, between the cover support
surface 252 of the sidewall 232 and the opposing surface 227 of the
cover member 220, between the cover support surface 254 of the
sidewall 234 and the opposing surface 227 of the cover member 220,
between the cover support surface 251 of the sidewall 231 and the
opposing surface 227 of the cover member 220, and the lateral
counter surface 260B of the counter portion 260 and the lateral
cover surface 223 of the cover member 220. Thus, the resin 70 is
disposed between the sidewalls 231-234 of the housing 210 and the
cover member 220 over the whole circumference of the housing 210.
Accordingly, the resin 70 allows the accommodation space S in the
laser module to be sealed for moisture prevention.
With regard to cross-sections that are parallel to the XZ-plane and
pass through the counter portion 260, the lateral counter surface
260A of the counter portion 260 and the lateral cover surface 221
of the cover member 220 are opposed to each other while the resin
70 is interposed therebetween. The cover support surfaces 253 and
252 of the sidewalls 233 and 232 and the opposing surface 227 of
the cover member 220 are opposed to each other while the resin 70
is interposed therebetween. The lateral cover surface 221 of the
cover member 220 and the lateral cover surface 222, which is
located on an opposite side of the lateral cover surface 221, are
exposed to an outside. In other words, the resin 70 is provided
only on one side of the cover member 220 (on the lateral cover
surface 221) in the X-direction, and the lateral cover surface 222
on the opposite side is exposed to the outside. Therefore, the
resin 70 located between the lateral counter surface 260A of the
counter portion 260 and the lateral cover surface 221 of the cover
member 220 can deform without any restriction in the X-direction.
Accordingly, when the resin 70 located between the lateral counter
surface 260A of the counter portion 260 and the lateral cover
surface 221 of the cover member 220 expands or shrinks in the
X-direction, deformation of the resin 70 exerts less influence on
the housing 221. Thus, the housing 210 is prevented from deforming.
As a result, the optical characteristics of the optical components
placed in the accommodation space S within the housing 210 are
prevented from being deteriorated. Such advantageous effects can be
attained in the same manner with regard to cross-sections that are
parallel to the YZ-plane and pass through the counter portion
260.
When a laser module thus constructed is manufactured, a resin 70 is
applied onto a resin application area shaded in FIG. 13 (the cover
support surface 251 of the sidewall 231, the lateral counter
surfaces 260B and 260A of the counter portion 260, the cover
support surface 253 of the sidewall 233, the cover support surface
252 of the sidewall 232, and the cover support surface 254 of the
sidewall 234). As with the above-described embodiments, an
ultraviolet curable resin can be used for the resin 70.
In a state in which the opposing surface 227 of the cover member
220 is opposed to the base portion 12 of the housing 210, the cover
member 220 is placed so as to face the lateral counter surface 260A
of the counter portion 260. The cover member 220 is placed so as to
face the lateral counter surface 260B of the counter portion 260.
Thus, the lateral cover surfaces 221 and 223 of the cover member
220 are brought into contact with the resin 70 applied onto the
lateral counter surfaces 260A and 260B. Furthermore, the cover
member 220 is pushed toward the cover support surfaces 251-254 of
the sidewalls 231-234. Thus, the opposing surface 227 of the cover
member 220 is brought into contact with the resin 70 applied onto
the cover support surfaces 251-254 of the sidewalls 231-234.
At that time, the cover member 220 can be positioned in the
X-direction by placing the cover member 220 so as to face the
lateral counter surface 260A of the counter portion 260. The cover
member 220 can be positioned in the Y-direction by placing the
cover member 220 so as to face the lateral counter surface 260B of
the counter portion 260. Thus, according to one or more
embodiments, the cover member 220 can be positioned with accuracy
on the XY-plane.
In this state, ultraviolet rays are irradiated to the resin 70 in
all possible directions with use of an ultraviolet irradiation
apparatus (UV furnace) or the like. At that time, the resin 70
located between the sidewalls 231-234 and the cover member 220
extends from an externally exposed portion along the YZ-plane, the
XZ-plane, or the XY-plane. Therefore, the resin 70 located between
the sidewalls 231-234 and the cover member 220 can be cured by
ultraviolet rays irradiated along the YZ-plane, the XZ-plane, or
the XY-plane. Therefore, all of the resin 70 located between the
sidewalls 231-234 and the cover member 220 can be cured by
ultraviolet rays irradiated from the outside.
According to one or more embodiments, the cover member 20 has a
uniform thickness in the Z-direction. In order to reduce the weight
of the laser module 1, however, the cover member 20 may be thinned
in the Z-direction. For example, as shown in FIG. 14, the thickness
of the lateral cover surface 22 of the cover member 20 may be made
less than the thickness of the lateral cover surface 21 located on
an opposite side of the lateral cover surface 22. Similarly, the
thickness of the lateral cover surface 24 may be made less than the
thickness of the lateral cover surface 23 located on an opposite
side of the lateral cover surface 24. In the embodiments
illustrated in FIGS. 6-14, the thickness of the lateral cover
surfaces on which no resin 70 is applied may be made less than the
lateral cover surface on the opposite side so as to reduce the
weight of the laser module.
Each of the above embodiments illustrates an example in which the
base portion and the sidewalls of the housing are integrally
formed. However, the base portion and the sidewalls may be provided
as separate members and assembled into the housing.
In the above embodiments, the resin 70 is formed between the
sidewalls of the housing and the cover member over the whole
circumference of the housing. However, the resin 70 does not need
to seal between the sidewalls of the housing and the cover member
over the whole circumference of the housing. Furthermore, the
sidewall and the cover member may be fixed to each other with use
of another fixation means and the resin 70.
In the aforementioned embodiments, two or more lateral counter
surfaces are formed. However, only one lateral counter surface may
be formed. In order to achieve accurate positioning on a plane, two
or more lateral counter surfaces may be formed to position the
cover member in two or more directions.
In the aforementioned embodiments, a laser module having a
semiconductor laser device as an optical component has been
described by way of example. Nevertheless, the present invention is
not limited to such an example. For example, the present invention
is also applicable to an optical transceiver module having a
photodiode used as an optical component to receive and convert
external light into electricity.
Although the disclosure has been described with respect to only a
limited number of embodiments, those skilled in the art, having
benefit of this disclosure, will appreciate that various other
embodiments may be devised without departing from the scope of the
present invention. Accordingly, the scope of the invention should
be limited only by the attached claims.
The present invention may be used for an optical module having a
housing including an optical component mounted thereon.
REFERENCE SIGNS LIST
1 Laser module (optical module)
10 Housing
12 Base portion
20 Cover member
21 Lateral cover surface (first lateral cover surface)
22 Lateral cover surface (second lateral cover surface)
23 Lateral cover surface (third lateral cover surface)
24 Lateral cover surface (fourth lateral cover surface)
25 Opposing surface
31 Sidewall (first sidewall)
32 Sidewall (second sidewall)
33 Sidewall (third sidewall)
34 Sidewall (fourth sidewall)
40 Semiconductor laser device
41, 42 Lens
44 Ferrule fixation portion
45 Ferrule
46 Optical fiber
51-54 Cover support surface
61-64 Counter portion
61A, 63A Lateral counter surface
70 Resin
101 Laser module
110 Housing
120 Cover member
121-128 Lateral cover surface
129 Opposing surface
131-134 Sidewall
151-154 Cover support surface
161, 163 Counter portion
161A, 161B, 163A, 163B Lateral counter surface
210 Housing
220 Cover member
221-226 Lateral cover surface
227 Opposing surface
231-234 Sidewall
251-254 Cover support surface
260 Counter portion
260A, 260B Lateral counter surface
310 Housing
331-334 Counter corner portion
C1-C4 Corner portion
S Accommodation space
* * * * *